Zettō Kanna is a straight sword, something you don’t expect to see in Japanese swords, with unique hilt comprised of purple floral patterns on a black and gold grip however unlike most western swords it lacks a guard. Its focus is being "unbendable" and "unbreakable". This blade is strongly based on the real life Dotanuki.
The retainers of this sword tend to rely on thrusts when battling in order to use all of it’s potential; it's ultimate technique, Hōfuku Zettō, consists in the user throw all his weight in a single slice/thrust in order to rely on it's hard edge to completely slash/pierce the foe.
It remains in possession of Kōmori Maniwa, until he fights Shichika Yasuri in Fujoushima on Volume one. After a brief battle where Shichika fails to break the sword, Togame informs him that he is prohibited from breaking the sword, later Shichika manage to defeat Kōmori with his first version of Shichika Hachiresu, retrieving the sword.
After being sent to the Shogunate it's then handed over to Hannyamaru, which retains it until his fight with Shichika in volume twelve, when it is finally broken in the middle of the fight.